/*

 * sflow.c

 *

 * Copyright (C) 2011-26 - ntop.org

 *

 * nDPI is free software: you can redistribute it and/or modify

 * it under the terms of the GNU Lesser General Public License as published by

 * the Free Software Foundation, either version 3 of the License, or

 * (at your option) any later version.

 *

 * nDPI is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public License

 * along with nDPI.  If not, see <http://www.gnu.org/licenses/>.

 *

 */

#include "ndpi_protocol_ids.h"

#define NDPI_CURRENT_PROTO NDPI_PROTOCOL_SFLOW

#include "ndpi_api.h"

#include "ndpi_private.h"

static void ndpi_search_sflow(struct ndpi_detection_module_struct *ndpi_struct, struct ndpi_flow_struct *flow)

{

  struct ndpi_packet_struct *packet = &ndpi_struct->packet;

  // const u_int8_t *packet_payload = packet->payload;

  u_int32_t payload_len = packet->payload_packet_len;

  NDPI_LOG_DBG(ndpi_struct, "search sflow\n");

  if((packet->udp != NULL)

     && (payload_len >= 24)

     /* Version */

     && ntohl(get_u_int32_t(packet->payload, 0)) == 0x00000005

     /* Agent Address type: IPv4 / IPv6 */

     && (ntohl(get_u_int32_t(packet->payload, 4)) == 0x00000001 ||

         ntohl(get_u_int32_t(packet->payload, 4)) == 0x00000002)) {

    NDPI_LOG_INFO(ndpi_struct, "found (probably) sflow\n");

    if (flow->packet_counter >= 2)

    {

      NDPI_LOG_INFO(ndpi_struct, "found sflow\n");

      ndpi_set_detected_protocol(ndpi_struct, flow,

                                 NDPI_PROTOCOL_SFLOW,

                                 NDPI_PROTOCOL_UNKNOWN,

                                 NDPI_CONFIDENCE_DPI);

    }

    return;

  }

  NDPI_EXCLUDE_DISSECTOR(ndpi_struct, flow);

}

void init_sflow_dissector(struct ndpi_detection_module_struct *ndpi_struct)

{

  ndpi_register_dissector("sFlow", ndpi_struct,

                     ndpi_search_sflow,

                     NDPI_SELECTION_BITMASK_PROTOCOL_V4_V6_UDP_WITH_PAYLOAD,

                     1, NDPI_PROTOCOL_SFLOW);

}